Method of producing zirconium halide



United States Patent METHOD OF PRODUCING ZIRCONIUM HALIDE Ivor E. Campbell, Gahanna, Ohio, assignor to the United States of America as represented by the Umted States Atomic Energy Commission No Drawing. Application November 13, 1953, Serial No. 392,071

2 Claims. (Cl. 23-87) This invention deals with a method of producing zirconium iodide, and in particular with a process based on the iodination of the carbonitride.

It has been customary heretofore first to produce zirconium from zirconium ores or other raw materials and then to convert the zirconium to the iodide by iodination. This involves quite a detour, which makes the process costly and ineflicient, and it has therefore been found desirable directly to iodinate intermediate zirconium-containing products as they are formed in the course of processing zirconium raw materials. One of the intermediate products frequently obtained in the processing of zirconium ores, for instance, is the zirconium carbonitride. It was found, though, that zirconium carbonitride, when heated to approximately 1000 C. and contacted with iodine vapor, reacts very little or not at all with the iodine, so that the yield was practically zero.

It is an object of this invention to provide a process by which zirconium carbonitride can be iodinated to a comparatively high degree.

It has been found that, if zirconium carbonitride at elevated temperature is first kept in contact with, or soaked in, a static iodine atmosphere for from 1 to 2 hours, iodination then proceeds easily at about 1000 to 1100C. in a current of iodine. The soaking operation appears to destroy a protective film which inhibits iodination, but the mechanism of this reaction is not fully understood and no explanation is offered for the effectiveness of this treatment.

No special equipment is required for this pretreatment and it may be carried out in any conventional iodination furnace. A furnace with a split-graphite-electrode heater similar to those used in chlorination of various oxides is suitable as an iodination furnace.

In the following, an example is given to illustrate the efiect of the soaking step according to this invention.

Example Zirconium carbonitride was heated to 1000 C. in a current of iodine vapor for a 4-hour period. Measurement of the weight of zirconium carbonitride before and after this treatment and examination of the exhaust vapors showed that no measurable quantities of zirconium tetraiodide had been formed.

Thereafter, the experiment was repeated under identical conditions except that, prior to the reaction step proper described in the preceding paragraph, the carbonitride was kept in contact with a static iodine atmosphere at 1000 C. for about 1 hour. When, after this pretreatment, an iodine current was introduced into the iodination furnace, a conversion of 3.0% of the iodine was established in a 4-hour iodination period. A 59% conversion of iodine to zirconium tetraiodide was obtained in a similar test at 1100 C., although no substantial iodination was obtained in a similar experiment when the soaking treatment was eliminated.

It will be understood that this invention is not to be limited to the details given herein but that it may be modified within the scope of the appended claims.

What is claimed is:

1. A process of producing zirconium iodide by reacting zirconium carbonitride with iodine, comprising heating the carbonitride to about 1000 C., soaking the heated carbonitride in a static atmosphere of iodine for approximately from 1 to 2 hours, then passing a current of iodine over the carbonitride heated to from 1000 to 1100 C. whereby the formation of zirconium iodide takes place.

2. The process of claim 1 wherein the iodination temperature is about 1100 C.

References Cited in the file of this patent UNITED STATES PATENTS 1,582,126 Cooper et al. Apr. 27, 1926 2,401,543 Brallier June 4, 1946 2,519,385 Loonam Aug. 22, 1950 OTHER REFERENCES I. W. Mellors, A Comprehensive Treatise on Inorganic and Theoretical Chem., vol. 2, page 66. Longmans, Green & Co., N. Y. 

1. A PROCESS OF PRODUCING ZIRCONIUM IODIDE BY REACTING ZIRCONIUM CARBONITRIDE WITH IODINE, COMPRISING HEATING THE CARBONITRIDE TO ABOUT 1000* C., SOAKING THE HEATED CARBONITRIDE IN A STATIC ATMOSPHERE OF IODINE FOR APPROXMATELY FROM 1 TO 2 HOURS, THEN PASSING A CURRENT OF IODINE OVER THE CARBONITRIDE HEATED TO FROM 1000 TO 1100* C. WHEREBY THE FORMATION OF ZIRCONIUM IODINE TAKES PLACE. 